Heat Link Issue - unable to turn off heating

[rvino-123]

I have a nest gen 3 recently installed a few days ago, right after the installation our engineer was able to show that the we could turn the heating on/off. However, a few hours after and despite programming the nest a certain way,  the heating continued working even when the current temperature was way above the target temperature (meaning it should be off). After some further investigating, it was apparent that we could switch hot water on/off but heating would not turn on. 

We had to wait and call out the engineer again who performed some diagnostic tests on it and concluded that the issue had to do with the heat link.  Obviously, not going to be a  free visit 😕 As explained by the engineer, the fault lies at the bridge between point 1 and 3. It never breaks but works fine for the hot water.

I am having issues rotating this image, but the issue lies with the diagram. The connection between points 1 and 3 does not break but should when the system doesn't demand heat.  Unfortunately, we think this can be only be resolved with a replacement heat link which will need to be installed again there is no issue with the thermostat. At the moment to turn off the heating, I need to lower the temperature on my boiler until it turns off. 

[Frustratedddd · Accepted solution]

Have you tried a factory reset? Sometimes this clears the problem. Your contacts are closed for some reason.

Contacts 1, 2, 3 are your heating contact, and normally 2 is the feed in.

Contact 1 under normal circumstances will be live, and contact 3 not. When called for heat, the reverse should happen. A neon screwdriver is the easiest method of testing the contacts switching.

Can you load a picture of the wiring connections?

[CristianC]

Hi @rvino-123,

Thanks for reaching out. Did the installer leave you a diagnostic report? I'd like to take a look at what tests he preformed. 

[CristianC]

Hello again. Just checking in. Do you still need my help?

[rvino-123]

Thanks for checking in and sorry for the late reply. Currently the system and heat link are working fine. Factory reset appeared to work. I can consider this issue resolved for now. 

[CristianC]

Hey @rvino-123. I'm happy to hear that you managed to resolve the issue. If anything comes up, feel free to create a new thread.